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Pollutants threaten marine life

Dr Crispin Halsall talks to the BBC's Share Planet programme about the impact of chemical pollutants on marine mammals and ocean wildlife.

The BBC's Radio 4 programme 'Shared Planet' explores issues concerning the conflict between an increasing human population and wildlife.

In the latest episode Dr Crispin Halsall, a Reader in Environmental Organic Chemistry at Lancaster Environment Centre, talks to the series presenter, Monty Don about how chemical pollutants created by human activity are spreading around the globe.

“The BBC approached me as they wanted a scientist who understood how these chemicals get into the environment and end up being distributed to remote reaches of the planet,” Crispin said.

“How does something you throw away in the middle of the UK end up in a sea creature on the other side of the world?

Look at the lifecycle

“The important thing is to look at the whole lifecycle of these chemicals, from test tube to landfill, and then how they get into the atmosphere and water courses of the world.

“We've known for some time that legacy chemicals like DDT and PCBs are widely distributed in the global environment. They possess chemical properties - a resistance to being broken down and an ability to accumulate in fats and lipids - that means they pose a threat to marine life, particularly to those at the top of the food chain.

“While efforts to curb the global production of these chemicals has been largely successful, there are an array of newer substances – chemicals with major commercial value – that have similar persistency and are also present in marine foodwebs.”

The BBC programme focussed on the stress these chemicals are putting on wildlife, particularly marine mammals, who are suffering diseases like cancer which were once extremely rare.

‘There is growing concern that these long-lived chemicals pose an additional stress on wildlife populations trying to adapt to climate change, and this is particularly relevant in remote Polar Regions where the effects of climate change are most noticeable,” Crispin continues

Balancing risks

“However one thing I wanted to get across is that these chemicals aren’t all bad. Many have brought great benefits to humans in terms of well-being, lifestyle and food production, and therefore a wholesale ban is difficult to achieve.

“Halogenated flame retardants are a case in point – these chemicals have probably saved thousands of lives but unfortunately they possess the very properties that result in their global dispersal and occurrence in wildlife.

“The onus is really on industry to be innovative - to produce new substances which serve a useful function but are environmentally benign. We have a long way to go!”